Brennan closed the apartment door and flipped the deadbolt shut. She hung her coat neatly in the closet and crouched to unzip her boots. Leaving them behind, she limped to the bathroom and turned on the shower.

As the water heated, she pulled off her jeans and sweater, then peeled off the lycra outfit underneath. She dumped all of the dirty clothes in the hamper, then stepped into the steaming shower.

She'd be sore tomorrow, but it was worth it.

BbB

The waitress filled his coffee cup as Booth opened the newspaper. For the third time that month, the lead story was about D.C.'s new superhero, who the press had nicknamed "Ninja Girl".

Somehow, she seemed to know when someone was in trouble and show up in time to intervene. The latest story was about a mugging, which ended with the perpetrator tied up with red tape, suffering from two cracked ribs and a broken arm.

The DC police had worked with the victim to get a description, and the sketch artist's picture took up the upper half of the front page.

Booth scoffed and turned the page. At least that yahoo wasn't his problem.

BbB

"We're going to be late."

Hodgins grinned at Zach. "Come on, Zach, live a little. The world won't end if you're ten minutes late one day."

"Dr. Brennan won't like it."

"Tell her it's my fault", Hodgins suggested.

"It is your fault."

"Then you won't even have to lie", Hodgins said. "Come on, help me get these soil samples and we'll be on our way."

BbB

"You're late, Zach." Brennan's disappointment was evident in her tone.

"It was Hodgins's fault", Zach explained.

Brennan's serious gaze settled on him. "You are responsible for being at work on time, regardless of Dr. Hodgins's inability to do so."

"Yes, Dr. Brennan", Zach answered, glaring at Hodgins.

"Come on, give the kid a break", Hodgins said. "I made him late. I wanted to stop by the scene of that mugging last night to get some samples."

"I was not aware that we were investigating a mugging", Brennan answered.

"We're not", Hodgins replied. "But if we could unmask Ninja Girl..."

"That's a terrible name."

Booth swiped his card in the badge reader and bounded up the steps. "What's a terrible name?"

"Ninja Girl", Brennan answered, her disgust at the moniker written on her face.

"Ugh", Booth replied. "Not you guys, too. The whole city seems to be talking about that vigilante."

"We have laws for a reason", Booth barked. "We have the constitution and due process and the right to a fair trial. No one should be able to take all of that away, not even if she's hot and runs around in tight clothes."

"Well, I'm going to unmask her", Hodgins said, "And then she'll stop running around making fools of the cops."

"Dr. Hodgins, we are not investigating this … 'Ninja Girl'", Brennan said. "And you do have work to do. I suggest you get started, given that you are already behind."

BbB

Brennan walked confidently through the lobby of her apartment building, careful to show no signs of injury. That had been a little too close, and she was afraid that she had seriously injured her ankle when she jumped into the alley.

She didn't let herself show any signs of pain until she was safely alone in her apartment. As soon as the door was locked behind her, she crumpled to the floor, moaning with the pain. She wasn't sure how long she sat there, curled up with her arms wrapped around her legs, but eventually, she had no choice but to move. She gingerly pulled off her boots, noting that her injured ankle was already discoloured and swollen, then limped to the bathroom. After a quick shower, she made her way back to the couch, where she applied ice to her throbbing ankle.

She was reasonably sure that it wasn't broken. It was, however, badly sprained, and there wasn't much she could do except rest it and continue to apply ice. Ninja Girl was out of commission for at least a week.

BbB

Her cell phone rang at a quarter to five, and Brennan dragged her aching body out of bed. She wrapped her ankle in a bandage for support and dressed in jeans, a tank top, and her Jeffersonian jumpsuit. By the time Booth arrived to pick her up, she was standing in the vestibule of her apartment building, waiting impatiently.

It was a short drive to the crime scene, followed by hours of crouching, kneeling, and contorting herself into difficult positions to photograph the scene and retrieve the body. By the time she was finally done, she was stiff, sore, and tired.

She walked to the truck as carefully as possible, but she knew she was limping. Naturally, Booth's eagle eyes didn't miss a thing. "You OK, Bones?"

She turned and looked at him, too tired to reply.

"You're limping", he explained, gesturing at her feet.

"Oh", she said, trying to think of a plausible excuse. "I twisted my ankle yesterday. It's just a little sore."

"Put some ice on it when you get home", Booth advised. "It'll feel better in no time."

BbB

Booth pulled his cash from the ATM and put it in his wallet. He snagged his receipt from the machine and walked through the door into the evening air.

It was a beautiful night, and he whistled to himself as he walked to his vehicle. As he fumbled in his pocket for his keys, he heard a scream, which was abruptly cut short. Hand going to his weapon, he started to run.

He slowed when he reached the corner, hugging the wall and peering around the corner to see what he was about to walk into.

To his surprise, he saw a woman dressed in a tight black outfit complete with a bright red cape. At her feet lay an unconscious man. Another man was whimpering in pain, his hands and feet bound together with red tape. Another woman huddled against the wall, her arms around a young child.

Booth pulled his badge from his pocket and, gun in hand, stepped around the corner. "Freeze! FBI!"

The woman in black started to run, cape billowing out behind her. He followed, only to lose her when she bounded over a chain-link fence. Disgruntled, he returned to the scene and waited for the DC cops to arrive.

BbB

It took him three days to realize where he'd seen her before. It wasn't, as he'd thought, the picture in the paper that made her look so familiar. No, it was hours spent driving, days spent interviewing suspects, months of working together.

He was going to throttle her.

He'd worked with her long enough to need proof, though, so his first step was a good, old-fashioned stake-out. He spent three weeks tracking her movements – when she left home, when she returned – and comparing them with sightings of Ninja Girl.

They all matched.

The next time she returned home, late at night, he followed her up to her apartment, reaching her floor just as her door clicked shut. He jogged down the hall and knocked, calling "I know you're there, Bones, open the door!"

There was silence, and he added, "I'll kick it down if I have to, Bones."

A few seconds later, he heard the deadbolt click. Brennan opened the door and asked, "What's going on? Do we have a case?"

He pushed past her, and she shut the door behind him.

Brennan leaned against the door and repeated, "Why are you here, Booth?"

He stalked towards her, stopping when he was close enough that she could feel his breath on her cheek. "I've noticed something, Bones."

She took a shuddering breath, unnerved at his closeness.

He continued, "Did you know that Ninja Girl only shows up when you're not home?"

Her forehead crinkled. "Really?"

"Really", he confirmed. "I've been watching you for three weeks, and it's true."

He slid his other hand under her shirt, and pushed it up until it was bunched under her armpits. He'd known what he'd find, but it was still a shock to see the tight black suit under her clothes. He stood there, stunned, until she wrenched away.

She walked over to the couch and sat, unzipping her boots and pulling them off. He collapsed onto the couch beside her and leaned forward, his head in his hands.

"I can't believe it."

She set her boot down on the floor and asked, "Why?"

He laughed ruefully. "That's my question. Why, Bones?"

She shrugged. "Don't you ever get tired of death, of only finding out about something terrible after it's already happened? It's … satisfying to stop crime before anyone is hurt."

"You could be hurt."

"I haven't been – not seriously. I find the element of surprise is very effective."

"But ..."

"I can handle myself, Booth. You know that." She stood in an obvious invitation for him to leave. "It's time for you to go home. We have work tomorrow."

He stood as well. "You know Hodgins is going to find out who you are."